Neil deGrasse Tyson has never been shy about separating fact from fiction, even when it comes to the sometimes fantastical world of Hollywood. (It’s because of the noted astrophysicist that James Cameron corrected the star field in one of Titanic’s most important scenes.) So it's hardly surprising that, in honor of Back to the Future Day, he took to Twitter to craft a multi-tweet report card on what Back to the Future II got right—and wrong—about what October 21, 2015 would look like.

The biggest takeaways? Hoverboards are coming, double neckties will never be a thing, and Tyson's not betting on the Cubs in the World Series.